ECU MERCEDES-BENZ C CLASS 2018 Service Manual

Display messagesPossible causes/consequences andMSolutions
FrontPassengerAir‐bag Enable dSeeOperator' sManual
The front-passenger fron tair bag is enabled during th ejourney, eve n
though :
Rachild, asmall adult or an objec tweighing less than th esystem' s
weigh tthreshold is locate don th efront-passenger seat
or
Rth efront-passenger seat is unoccupied
The system may detec tobjects or force sapplyin gadditional weigh ton
th eseat .
GWARNIN G
The front-passenger fron tair bag may deploy unintentionally.
There is an increased ris kof injury.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XSwitchth eignition off .
XOpenth efront-passenger door .
XRemove thechild and th echild restrain tsystem from th efront-
passenger seat .
XMakesur ethat there are no objects on th eseat addin gto th e
weight.
The system might otherwise detec tth eadditional weigh tand inter-
pre tth eseat occupant's weigh tas greate rthan it actually is.
XKee pth eseat unoccupied ,close th efront-passenger door and
switch on th eignition .
XObserveth ePASSENGER AI RBA Gindicator lamp sin th ecenter
console and th emultifunction display and chec kth efollowing:
Seat unoccupied and ignition switched on :
Raself-diagnosis is carrie dout .The PASSENGER AI RBA GOF Fand
PASSENGER AI RBA GON indicator lamp smus tligh tup simulta-
neousl yfor approximately six seconds
Rth ePASSENGER AI RBA GOF Findicator lamp mus tthen ligh tup
and remain lit after th eself-diagnosis .If th eindicator lamp is on ,
OCS has disabled th efront-passenger fron tair bag (
Ypage 52)
Rthedisplay message sFront Passenger Airbag Enable dSee Operator'sManualor Front Passenger Airbag Dis ‐abled See Operator'sManualmus tno tappear in th emulti-
function display
XWait for aperiod of at least 60 seconds until th enecessar ysystem
checks hav ebeen completed.
XMak esur ethat th edisplay message sdo no tappear in th emulti-
function display.
If these condition sare fulfilled ,th efront-passenger seat can be occu-
pied again .Whether th ePASSENGER AI RBA GOF Findicator lamp
remain slit or goe sout depend son how OCS classifies th eoccupant .
If th econdition sare no tfulfilled ,th esystem is no toperating correctly.
XVisit aqualified specialist workshop immediately.
Display messages24 1
On-board computer and displays
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Engine
Display messagesPossible causes/consequences andMSolutions
+
CheckCoolantLevelSee Operator's Man‐ual
The coolant level is too low.
!Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
XAdd coolant, observing the warning notes before doing so
(Ypage 306).
If you have to add coolant frequently:
XContact a qualified specialist workshop and have the engine cooling
system checked.
?The fan motor is malfunctioning.
XIf the coolant temperature is below the red marking in the coolant
temperature gauge, drive to the nearest qualified specialist work-
shop.
XAvoid heavy loads on the engine as you do so, e.g. driving in moun-
tainous terrain and stop-and-go traffic.
?
Coolant Too HotStop Vehicle TurnEngine Off
The coolant is too hot.
A warning tone also sounds.
GWARNING
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to catch
fire.
Steam from the overheated engine can also cause serious burns which
can occur just by opening the hood.
There is a risk of injury.
XPull over and stop the vehicle safely and switch off the engine, pay- ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 161).
XWait until the engine has cooled down.
XMake sure that the air supply to the engine radiator is not blocked,
e.g. by snow, slush or ice.
XDo not start the engine again until the display message goes out and
the coolant temperature gauge is below the red marking. Other-
wise, the engine could be damaged.
XPay attention to the coolant temperature gauge.
If the temperature increases again:
XVisit a qualified specialist workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature gauge may rise to the red marking.
Display messages243
On-board computer and displays
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Display messagesPossible causes/consequences andMSolutions
#
See Operator'sMan ‐ual
The battery is no tbein gcharged.
A warning tone also sounds.
Possibl ecauses are:
Radefective alternato r
Ratorn poly-V-belt
Ramalfunction in th eelectronics
!Do no tcontinu edriving. The engin ecould otherwise overheat.
XPull ove rand stop th evehicl esafely and switch off th eengine, pay-
ing attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XConsult aqualified specialist workshop .
#
StopVehicl eSeeOperator' sManual
The battery is no longer bein gcharged and th econdition of charg eis
to olow.
A warning tone also sounds.
XPull ove rand stop th evehicl esafely and switch off th eengine, pay-
ing attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XObserv eth einstruction sin th e# See Operator' sManualdisplay message .
XConsultaqualified specialist workshop .
#
StopVehicl eLeaveEngine Runnin g
The battery condition of charg eis to olow.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XLeav eth eengin erunning.
XWait until th edisplay message disappear sbefore pullin gaway.
#
Start Engine SeeOperator' sManual
The engin eis switched off and th econdition of charg eis to olow.
XSwitc hoff electrical consumer sthat you do no tneed, suc has th e
rear window defroste rand interior lighting .
XLeaveth eengin erunnin gfor afew minute sor drive alon gdistance.
The battery is bein gcharged.
244Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
4
CheckEngineOilAtNextRefueling
The engin eoil level has dropped to th eminimum level.
A warning tone also sounds.
!Avoid lon gjourneys wit hto olittl eengin eoil. The engin ewill oth-
erwise be damaged.
XChec kth eoil level when next refueling, at th elatest (Ypage 305).
XIf necessary, add engin eoil (Ypage 305).
If you have to ad dengin eoil frequently:
XContac t aqualified specialist workshop and hav eth eengin e
checked.
Information on approve dengin eoils can be obtained from aqualified
specialist workshop or on th eInternet at http://bevo.mercedes -
benz.co m.
4
Check Engine OilLevel(Add1quart)(USA)Check EngineOil Level (Add 1Liter)(Canada)
Mercedes-AMG C 63 vehicles:
The engine oil level has dropped to the minimum level.
!Avoid long journeys with too little engine oil. The engine will oth-
erwise be damaged.
XCheck the oil level when next refueling, at the latest (Ypage 305).
XIf necessary, add engine oil (Ypage 305).
If you have to add engine oil frequently:
XContact a qualified specialist workshop and have the engine
checked.
Information on approved engine oils can be obtained from a qualified
specialist workshop or on the Internet at http://bevo.mercedes-
benz.com.
4
Engine Oil LevelLow Stop VehicleTurn Engine Off
Mercedes-AMG C 63 vehicles:
The engine oil level is too low. There is a risk of engine damage.
XPull over and stop the vehicle safely and switch off the engine, pay-
ing attention to road and traffic conditions.
XSecure the vehicle against rolling away (Ypage 161).
XCheck the engine oil level (Ypage 305).
XIf necessary, add engine oil (Ypage 305).
8
Fuel Level Low
The fuel level has dropped into the reserve range.
XRefuel at the nearest gas station.
CThere is only a very small amount of fuel in the fuel tank.
XRefuel at the nearest gas station without fail.
Display messages245
On-board computer and displays
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Drivingsystems
Display messagesPossible causes/consequences an dMSolutions
À
ATTENTION ASSIST :Take a Break!
Based on certain criteria, ATTENTION ASSIST has detecte dfatigue or
a lac kof concentration on th epar tof th edriver . Awarnin gtone also
sounds.
XIf necessary, take abreak .
Durin glon gjourneys, take regular break sin goo dtime so you get
enough rest.
À
ATTENTION ASSISTInoperative
ATTENTION ASSIST is inoperative .
XVisitaqualified specialis tworkshop .
¨
VehicleRising
The vehicle is risin gto th elevel you hav eselected.
¨
Vehicl eRisingPlease Wai t
The vehicle level is to olow when th evehicle is stationary. Awarnin g
tone also sounds.
XDo no tpull away.
The vehicle level is set when th edisplay messag edisappears .
¨
StopVehicl eVehi‐cle Too Low
You hav epulle daway whil eth evehicle level is still to olow.
AIRMATIC set sth evehicle to th eselecte dlevel after ashort period.
XPull over and stop th evehicle safely as soo nas possible, payin g
attention to road and traffic conditions.
XSecur eth evehicle against rollin gaway (Ypage 161).
XWait until th edisplay messag edisappears befor epulling away.
AIRMATIC is malfunctioning. Awarnin gtone also sounds.
XDo no tdrive at speeds abov e50 mph (80 km/h).
XMak eonly slight steerin gmovements .Otherwise ,th efron tfender
or th etires could be damaged if th esteerin gmovemen tis to olarge.
XListe nfo rscrapin gsounds.
XPull over and stop th evehicle safely, payin gattention to road and
traffic conditions, and set ahigher vehicle level.
Dependin gon th emalfunction ,it may be possible to rais eth evehi-
cle.
XVisit aqualified specialis tworkshop .
¨
Malfunction
The AIRMATIC function is restricted. The vehicle' shandlin gcharac -
teristics may be affected.
XDo no tdrive at speeds abov e50 mph (80 km/h).
XVisit aqualified specialis tworkshop .
Display messages247
On-board computer and displays
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Display messagesPossible causes/consequences andMSolutions
LaneKeepin gAssistCurrently Unavaila‐ble See Operator' sManualorActiveLan eKeepin gAssistCurrently Unavaila‐ble See Operator' sManual
LaneKeepin gAssis tor Active Lan eKeepin gAssis tis deactivated and
temporarily inoperative.
Possibl ecauses are:
RThe windshield in th ecamera' sfield of vision is dirty.
RVisibilit yis impaire ddue to heav yrain ,snow or fog .
RThere havebeen no lan emarking sfor an extended period
RThe lan emarking sare wor naway, dark or covered up, e.g. by dir tor
snow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Lan eKeepin gAssis tor Active Lan eKeepin gAssis tis operational
again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XClean th ewindshield.
Lan eKeepin gAssistInoperativeor
ActiveLan eKeepin gAssist Inoperative
LaneKeepin gAssis tor Active Lan eKeepin gAssis tis malfunctioning .
XVisitaqualified specialist workshop .
Blind SpotAssistCurrently Unavaila‐ble See Operator' sManualorActiveBlind Spo tAssistCurrently Unavaila‐ble See Operator' sManual
Blind Spot Assistor Active Blind Spot Assis tis temporarily inoperative.
Possibl ecauses are:
RThe radar sensor system is outside th eoperating temperature
range.
RThe radar sensor system is temporarily inoperative, e.g. due to
electromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Blind Spot Assis tor Active Blind Spot Assis tis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XRestart th eengine.
Blind Spo tAssistInoperativeor
Active Blind Spo t
Assist Inoperative
Blind Spot Assistor Active Blind Spot Assis tis malfunctioning .
XVisitaqualified specialist workshop .
ParkingPilot Can ‐celedThe driver's door is open .
XRepeat theparking gap measuremen tand parking process wit hth e
driver's door closed .
248Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
Distance Pilot NowAvailableDistancePilo tDISTRONI Cis operational again after having been tem-
porarily unavailable .You can no wreactivat eDistanc ePilo t
DISTRONI C (
Ypage 173).
Distance Pilot Cur ‐rently UnavailableSee Operator'sMan ‐ual
Distanc ePilo tDISTRONI Cis temporarily inoperative.
Steering Pilo tis also temporarily inoperative.
Possibl ecauses are:
RThe radar sensor system is temporarily inoperative, e.g. due to
electromagneti cradiation emitted by nearby TV or radi ostation sor
other source sof electromagneti cradiation .
RThe system is outside th eoperating temperature range.
RThe on-boar dvoltag eis to olow.
A warning tone also sounds.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Distanc ePilo tDISTRONI Cis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XRestart th eengine.
DistancePilotInop‐erativ eDistanc ePilo tDISTRONI Cis malfunctioning .
The followin gmay hav ealso failed:
RActive Brake Assis twit hcross-traffic function
RSteering Pilo t
A warning tone also sounds.
XVisit aqualified specialist workshop .
Distance Pilot Sus‐pendedYou havedepressed th eaccelerato rpedal .Distanc ePilo tDISTRONI C
is no longer controllin gth espeed of th evehicle.
XRemove your foo tfrom th eaccelerato rpedal .
Distance Pilot- - - mphAcondition for activating Distanc ePilo tDISTRONI Chas no tbeen met .
XCheckth eactivation condition sfor Distanc ePilo tDISTRONI C
(Ypage 173).
250Display messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
Steering Pilot Cur‐rently UnavailableSee Operator'sMan ‐ual
Steering Pilo tis temporarily inoperative.
Possibl ecauses are:
RThe windshield in th ecamera' sfield of vision is dirty.
RVisibilit yis impaire ddue to heav yrain ,snow or fog .
RThere havebeen no lan emarking sfor an extended period.
RThe lan emarking sare wor naway, dark or covered up, e.g. by dir tor
snow.
Whe nth ecauses state dabov eno longer apply, th edisplay message
disappears.
Steering Pilo tis operational again .
If th edisplay message does no tdisappear :
XPull overand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XClean th ewindshield.
SteeringPilotInop‐erativ eSteering Pilo tis malfunctioning .
However, th eDistanc ePilo tDISTRONI Cfunction sare still available.
A warning tone also sounds.
XVisit aqualified specialist workshop .
CruiseControlInop‐erativeCruisecontrol is malfunctioning .
A warning tone also sounds.
XVisit aqualified specialist workshop .
Cruise Control- - -mph
RAcondition for activating cruise control has no tbeen met .
You hav etried to store aspeed belo w20 mph (30 km/h), for exam-
ple.
RES P®is deactivated. The yello wES P®OF Fwarning lamp is lit .
XIf conditionspermit ,drive faste rthan 20 mph (30 km/h )and store
th espeed.
or
XChec kth eactivation condition sfor cruise control (Ypage 169).
or
XReactivat eES P®(Ypage 222).
or
XReactivat eES P®in Mercedes-AMG vehicles (Ypage 71).
Cruise Contro lOffCruis econtrol has been deactivated.
If awarning tone also sounds, cruise control has deactivated auto -
matically (
Ypage 169).
Display messages251
On-board computer and displays
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Tires
Display messagesPossible causes/consequences andMSolutions
CheckTirePressureSoonCanada only:
The tire pressure loss warning system has detected a significant loss
in pressure.
A warning tone also sounds.
Possible causes:
Ryou have changed the positions of the wheels and tires or installed
new wheels and tires
Rthe tire pressure in one or more tires has dropped significantly
GWARNING
Tire pressures that are too low pose the following hazards:
Rthey may burst, especially as the load and vehicle speed increase.
Rthey may wear excessively and/or unevenly, which may greatly
impair tire traction.
Rthe driving characteristics, as well as steering and braking, may be
greatly impaired.
There is a risk of an accident.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
XSecure the vehicle against rolling away (Ypage 161).
XCheck the tires and, if necessary, follow the instructions for a flat
tire (Ypage 317).
XCheck the tire pressures and, if necessary, correct the tire pressure.
XRestart the tire pressure loss warning system when the tire pres-
sure is correct (Ypage 340).
CheckTirePressureThen Restart RunFlat Indicator
Canada only:
The tire pressure loss warning system generated a display message
and has not been restarted since.
XSet the correct tire pressure in all four tires.
XRestart the tire pressure loss warning system (Ypage 340).
Run Flat IndicatorInoperativeCanada only:
The tire pressure loss warning system is faulty.
XVisit a qualified specialist workshop.
PleaseCorrectTirePressureThe tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
XCheck the tire pressures at the next opportunity (Ypage 342).
XIf necessary, correct the tire pressure.
XRestart the tire pressure monitor (Ypage 342).
252Displa y messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
Check TiresThe tire pressurein on eor mor etires has dropped significantly. The
whee lposition is displayed in th emultifunction display.
A warning tone also sounds.
GWARNIN G
Tir epressures that are to olow pos eth efollowin ghazards :
Rthey may burst, especially as th eload and vehicl espeed increase.
Rthey may wear excessivel yand/o runevenly, whic hmay greatl y
impair tire traction .
Rthedrivin gcharacteristics ,as well as steering and braking ,may be
greatl yimpaired.
There is aris kof an accident.
XStop th evehicl ewithout making any sudden steering or braking
maneuvers .Pay attention to th etraffic condition sas you do so.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XCheckth etires and ,if necessary, follow th einstruction sfor aflat
tire (Ypage 317).
XChec kth etire pressur e (Ypage 342).
XIf necessary, correc tth etire pressure.
Warnin gTir eMal ‐functionThe tire pressur ein on eor mor etires has dropped suddenly. The whee l
position is shown in th emultifunction display.
GWARNIN G
Drivin gwit h a flat tire poses aris kof th efollowin ghazards :
Raflat tire affects th eabilit yto steer or brak eth evehicl e
Ryou could lose control of th evehicl e
Rcontinued drivin gwit h a flat tire will caus eexcessive heat build-up
and possibl y afire
There is aris kof an accident.
XStop th evehicl ewithout making any sudden steering or braking
maneuvers .Pay attention to th etraffic condition sas you do so.
XSecur eth evehicl eagainst rollin gaway (Ypage 161).
XCheckth etires and ,if necessary, follow th einstruction sfor aflat
tire (Ypage 317).
TirePress.Monito rCurrently Unavaila‐ble
Becausethere is interferenc efrom astron gsource of radi owaves, no
signals from th etire pressur esensor sare detected. The tire pressur e
monitor is temporarily malfunctioning .
XDrive on.
The tire pressur emonitor restarts automatically as soo nas th e
problem has been resolved.
TirePress .Sen ‐sor(s) Missin gThere is no signal from th etire pressur esensor of on eor several tires .
The pressur eof th eaffecte dtire is no tdisplayed in th emultifunction
display.
XHav eth efault ytire pressur esensor replace dat aqualified special -
ist workshop .
Display messages253
On-board computer and displays
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